What is the pH of $10^{-8} \mathrm{MHCl}$ solution?
What is the pH of $10^{-8} \mathrm{MHCl}$ solution?
8
7
$< 7$
$\gt8$
Solution
$10^{-8} \mathrm{M}$ indicates a very dilute solution.
Thus, $\left[\mathrm{H}^{+}\right]$from water cannot be ignored.
But dissociation of water is suppressed due to common ion effect.
$\left[\mathrm{H}^{+}\right] \neq 10^{-7}$, but less than $10^{-7}$.
Hence, pH of $10^{-8} \mathrm{M}$ of HCl is less than 7 .